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    <title>Document</title>
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    <script>
        /* 
            1. 立即执行函数：函数声明后，直接调用的函数。
            2. 语法结构：
                (function(形参){

                })(实参);
            3. 语法结构2：
                (function(形参){

                }(实参));
            4. 立即执行函数的变量是局部变量    
        */
        function cook() {
            console.log('清蒸鲈鱼');
        }
        cook();

        (function play(uname) {
            console.log(uname + '看电影');
        })('eason');

        (function eat(uname) {
            var address = "郑州";
            console.log(uname + "吃火锅");
            console.log(address);
        }('jay'));

        console.log(address);
    </script>
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